Mercury mark 6a disassembly woes

[lftmx3]

Wow, This motor has been a real pain to tear down. It looks as if it has never been serviced over its entire life. If there is a positive to this, it’s all the original properly sized hardware is still here. I’m trying to remove the powerhead from the cowl to rebuild the carb and fuel pump. To do this I’ve removed the lower section up to the swivel bracket. I CANNOT for the life of me get the upper housing piece to slide off the powerhead. Ive tried heat, cold, copius pb blaster. Nothing seems to make it budge, am I forgetting to take something else off first or is it really stuck!?

[dave-bernard]

carb comes off without removing the powerhead. don’t forget the filter behind the fuel connector. the fuel pump can be done lso BUT very hard. I thro that pump away it has small check valves. and add a later large valve pump from later 60’s up to 20 hp. remount it where you like.

[Buccaneer]

Kenny, I can email you a manual to covers all the procedures if you PM
me your email.

Prepare to be boarded!

[lftmx3]

that would be great! pm’d thanks

[jeff-register]

Your motor is like the kf5 motor. Mine was a royal pain to build and GET apart. The lower bearing & seal are the worst to change but it is possible. Your lower shroud makes it harder to do anything. Pay very close to details while working on it.

[lftmx3]

yes the top housing piece is preventing me from getting any further. I’d like to get the cowl off for cleaning and painting. If i hit it with a deadblow extremely hard I can make it rotate about a quarter inch. Probably the most frustrating part is how the service manual makes it so simple. Just remove the "special slotted screw" loosen co-pilot and presto! remove the power head from the swivel bracket… 😡

[billw]

The Mark 6 is one of those Mercs that gave all Mercs a bad name. It’s a tough motor to work on, in almost every aspect. Dave is right; you can take the carb off without removing the power head.

As for the piece holding you back, if you have really given it everything you have, you might consider getting a ratty parts motor and saw it apart, to save that one piece; then saw and split the one piece off your good motor. Since the lower units are often junk on these motors, finding a ratty parts donor shouldn’t be a problem.

The good news is that, when you’re FINALLY done, they run great….just as smooth and quiet as any OMC ever was.

Long live American manufacturing!

[Buccaneer]

Kenny, what exactly do you mean by " upper housing piece to slide off the powerhead" ?
What is the upper housing piece?
If I remember correctly, to get the lower cowling off, you have to pull the
power head / swivel tube out of the transom mount.

Prepare to be boarded!

[lftmx3]

quote Buccaneer:

Kenny, what exactly do you mean by ” upper housing piece to slide off the powerhead” ?
What is the upper housing piece?
If I remember correctly, to get the lower cowling off, you have to pull the
power head / swivel tube out of the transom mount.

[lftmx3]

I’ve given up after a small piece of the casting around the screw hole broke off today from too much messing with. Pretty much every surface inside the lower housing is covered in a very sticky gunk that can only be scraped off, I’m thinking that’s what was making it so difficult. Oh, well- I will just have to live with a dirty cowling.

[Author]

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